Chemical vapor deposition (CVD) and atomic layer deposition (ALD) provide methods for forming metal-containing layers on target substrates by supplying gases containing metal compounds to a deposition chamber or other deposition equipment. They have been widely used to manufacture electronic devices, semiconductor devices, display devices, and so on. Particularly, the semiconductor industry needs novel metal compounds and/or compositions for depositing metal-containing layers, such as metal layers, metal silicide layers, metal oxide layers, and metal nitride layers with desirable properties.
Amidinate compounds of nickel or cobalt have been used as precursors for ALD [B. S. Lim, A. Rahtu, J. S. Park, and R. G. Gordon, Inorganic Chemistry, 42, 7951 (2003)]. However, compositions having a high content of the amidinate compounds are in a solid state at room temperature and thus are not suitable for volume production of semiconductor devices using CVD or ALD.
Carbonyl compounds of cobalt or nickel are also in solid state at room temperature and thus not suitable for volume production of semiconductor devices using CVD or ALD. A few liquid cobalt precursors such as dicobalt hexacarbonyl tert-butylacetylene (CCTBA) or cyclopentadielycobalt dicarbonyl [(C5H5)Co(CO)2] are available commercially; however, they have to be used at a relatively low deposition temperature because they are not thermally stable. Few liquid nickel precursors are known and none is available commercially. And thus the semiconductor industry needs a liquid precursor composition for vapor deposition of cobalt- or nickel-containing layers.